Patent Document 1 (shown below) discloses an oil pressure control device for controlling a continuously variable transmission that includes a drive pulley, a driven pulley, and a belt wound around the two pulleys. The oil pressure control device controls belt pinching pressures (side pressures) of the drive pulley and the driven pulley of the continuously variable transmission. The drive pulley includes two cylinder chambers for generating a belt pinching pressure, and the driven pulley includes one cylinder chamber for generating a belt pinching pressure. Therefore, in a state where oil pressures to be supplied to the cylinder chambers of the pulleys are equal to each other, an axial thrust for generating the belt pinching pressure in the drive pulley becomes twice as large as an axial thrust for generating the belt pinching pressure in the driven pulley, and a transmission ratio is reduced (changed in a direction toward a higher-speed transmission ratio).